Monique Coleman was one of the first celebrities to share her support for Vanessa and her younger sister, 20-year-old Stella Hudgens, writing, "My deepest condolences @VanessaHudgens @stellahudgens. I love you both so much! You're in my thoughts & prayers."

As ET previously reported, Vanessa asked her followers to pray for her dad's healing over Instagram last July, announcing one month later that he was sick with stage 4 cancer at the Industry Dance Awards in Los Angeles. The news came less than one year after her boyfriend, Arrow star Austin Butler, lost his mother to cancer in September 2014. No other details about Greg's death at age 65 have been given yet.

In addition to her former co-stars, many other celebrities, friends and fans also took to social media to send prayers to the Hudgens family and wish Vanessa good luck in the production, which airs on FOX at 7 p.m. ET.